Ctenobactrites isogramma

Ctenobactrites is a genus of cephalopod under the order of Bactritida, an order rarely found in Western Pennsylvanian rocks. Ctenobactrites differs from Bactrites only by having a coarse transverse lirae (Mapes 1979). While I have found these intact, I have yet to find a suitable steinkern for collection. This specimenRead More →

While performing extensive research on the Paleozoic shark genus Petalodus, I uncovered a large number of holotype specimens. Yet, in conducting the search there are still a couple that I have not been able to locate. This is not surprising, all the missing holotypes were described during the 19th century,Read More →